Process of hardening the surface of mastic structures



1936- E. w. SCRIPTURE'JR 2,062,615

PROCESS OF HARDENING THE SURFACE OF MASTTC STRUCTURES Filed April 3,1955 cement and 7 ran concrc Z6 Patented Dec. .1, 1 936 PATENIV' OFFICEPROCESS OF HARDENING THE SURFACE OF MASTIC STRUCTURES Edward W.vScripture, In, Cleveland, Ohio, as-

Master Bllfl signer to The ders Company,

Cleveland, Ohio, a corporation of Ohio Application April 3, 1935, SerialNo. 14,526

15 claims.

This invention relates to mastic and masticsurfaced structures, such as,floors, driveways, walks, walls, ceilings, roofs and the like; andparticularly to such structures as are subject to 5 heavy wear, likefloors, walks and roadways, or to structures which are exposed to water,oils and chemicals, in which percolation of the aforesaid materials isundesirable by reason of disintegration, contamination or mechanicalweakening of lo the-mastic material of the structure.

It is a well-known fact that ordinary mastic structures by reason oftheir mechanically weak, relatively soft, crumbly character, are notparticularly well adapted for wearing surfaces although they have beenused to aconslderable extent for this purpose, largely by reason of theinexpensiveness of the materials employed or the ease with which theymay be laid, both upon new and existent structures formed from variousmaterials, as for example, stone, brick, concrete and wood. In additionto the items of ease of application and low material cost, masticfacings or surfaces are also employed by reason of their sound-deadeningproperties, their resiliency and their low coeflicient of heattransmission, which make them particularly well adapted for the floorsof buildings.

Another objection to the use of mastic surfaces is the difliculty incoloring such surfaces as paints with an oil vehicle soften and dissolvethe asphalt binder of mastic structure and the color is dulled, stainedor obliterated by reason of the paint mixing with the asphalt which itdissolves. If the mastic material is to be integrally colored, as forexample, by mixing dry pigments therewith prior to the laying of thematerial, the high percentage of pigments necessary to be employedoperates to weaken the structure, and even under the best j conditions,it is next to impossible to obtain sharp, 40 clear colors or tocompletely hide the asphalt base so that the colors that are obtainedare of a dull and non-descript character.

The object of the present invention is the provision of a process forimparting the requisite hardness, impenetrability and wearing qualitiesto a structure of this nature, with the employment of a minimum amountof material; the provision of a method for hardening or indurating thesurface layer of such a structure so as to render it-resistant to theaction of many chemicals and chemical solutions; the provision with theuse of a small quantity of pulverized metal,

. of a mastic structure which shall be resistant to abrasion ordisintegration; the provision of a 66 method whereby all of the materialmay be employed without waste; the provision of a mastic structure whosesurface shall be smooth, lasting and attractive; the provision of a.mastic structure having an integrally colored s'urface or a surfacewhich may be colored as desired by 5' painting; the provision of astructure of the character described, having a hardened surface whichmay be polished or otherwise treated to give it a smooth, glossysurface; and the process of treating the surface of an old structurewith a comparatively thin surface coating of material which may bereadily bonded to the old structure and which has an integrally formedhard, compact, dense surface which is highly resistant to moisture,chemicals and wear, such surface being of a wholly different characterfrom that of the body of the coating or surfacing material; theprovision of a method for integrally uniting two structures ofdissimilar character which normally are non-adherent, with respect toeach other} the provision of an integrally formed structure having arelatively soft, resilient base and a relatively hard surface of a com--position which normally will not adhere to the composition forming thebase; while further objects and advantages of the invention will becomeapparent in the course of the following description and claims.

The drawing accompanying and forming a part of this applicationillustrates the method of surfacing an existent structure, as forexample, concrete by the [use of the method described in thisapplication. The drawing illustrates a portion of a built-up sectionalstructure having a concrete base I with a bonding coat 2 of one or morecoats of asphalt primer, a mastic facing 3 and a hard surface 4 ofcement and iron particles which are thoroughly worked into the masticmaterial so as to form an integral part thereof, and to provide a hard,dense, wear resistant surface for the mastic facing. Particles of othermetals, as for example, copper, nickel and their ferrous alloys, areuseful for this purpose; iron being preferred by reason of itsrelatively low cost.

This invention is primarily concerned with the treatment of the exposedor wearing surfaces of a mastic structure. Structures of this sortordinarily are supported, though not necessarily so, by a base orfoundation wall of some sort and in the ensuing description, referenceis made to such base largely because it must be taken into consideration.in the procedure most commonly encountered.

In practicing the invention, the surface of the 55 Ill floated and thenfloated structure to be treated may be formed from a variety ofmaterials, as for example, stone, brick, concrete and wood. To such asurface after first being cleaned, a bond in the form of one or morecoats of asphalt primer is first applied and over this is laid anemulsified asphalt mix comprising, for example, two parts by volume ofemulsified asphalt which may include a slight amount of clay, one partby volume of hydraulic cement, eight parts by volume of graded aggregatewhich may be formed from two parts by volume of sand and six parts byvolume of aggregate ranging in size between three-eights of an inch andfiveeighths of an inch in diameter. Just enough water is added to themix to allow it to be readily worked.

.After the mix has been spread upon the surface to be covered, it istamped, screeded and then mechanically floated. Immediately after thefloating operation, a dry shake comprising two parts by weight ofmetallic aggregate and one part by weight of fresh hydraulic cement isapplied to the surface which is again mechanically again. The surface isthen gone over with a steel trowel, after which it is allowed to setpartially and then troweled again to burnish the surface.

After the burnishing operation, the surface is cured by covering it withsome material, as for example, paper, sand or straw to prevent the toorapid evaporation of the water from the structure which may causefracture or crazing of the surface of the structure. After the structurehas set, it will be found that the mastic structure has an integrallyformed, hard, wear resistant, dense, impermeable surface. The surface soformed may be treated with wax, varnish, paint or other protective ordecorative coatings.

The mastic structure so formed has the fol-. lowing advantages over anordinary mastic structure; its surface is highly resistant to wear; itwill support heavy objects. without deformation or marring of itssurface. The application of the mixtureof cement and iron particles tothe surface ofthe structure absorbs water and de-' creases the tendencyof the mastic material to shrinkage; it retards drying of the masticstruc-. ture and thus improves curing and minimizing cracking; iteliminates the operation of rolling the mastic structure, whichoperation is usually performed just after the structure has set; theelimination of the rolling operation preserves the structure of thecement which is used in theasphalt mix, thus increasing the mechanicalstrength of the structure.

The surface so formed, protects the underlying asphalt fromdisintegration by oils, water and chemical solutions. The surface of thestructure may be integrally colored by use of colored metallicaggregates. The surface may be readily treated with wax, paint orprotective coatings which ordinarily could not be applied to the masticstructure.

The proportions of the asphalt mix may be varied within certain limitsasis well understood by those skilled in the art of handling masticmaterials. The shake which is applied to the surface of the masticstructure also may be varied over rather wide limits, as for example,from one to three parts by'weight of metallic aggregate may be used withone part by weight of cement. The metallic aggregate is preferablyformed from clean angular iron particles which will pass through atwenty mesh screen. A small amount of fine powder may be added to themetallic par- .sodium sulphate, etc., may be metallic particles may becolored or uncolored.

When mixed with cement and used in the manner described, the ironparticles are covered with a thin coating of cement which prevents theiroxidation.

It has-been found in practice that it is diiiicult use ametallicaggregate as a dry shake and to properly work it into thesurface without the use of excess water which causes crazing, checkingand shrinkage. The use of a plasticizing agent as suggested, obviatesthe need of additional or excess water and greatly facilitates andreduces the labor of working the dry shake into the mastic structure.

No novelty is claimed for the mastic composition perse, disclosed hereinnor for the process involving its use prior to the step of adding cementand metallic particles to the surface of a structure formed from suchmaterials. The prior art shows compositions of matter comprising cementand fine metallic iron particles for use in finishing the surface ofconcrete structures, as for example, U. S. Patent No. 1,113,555 issuedOctober 13, 1914, to F. M. Haldeman for The prior art also showsprocesses for using such material in hardening or case-hardening thesurface of concrete structures, as for example, U. 8. Patent No.1,113,112 issu S. W. Flesheim for Process for hardening concretestructures.

My invention resides in the new and unexpected discovery that suchcompositions and such processes are applicable to'the treatment ofmastic structures and that a technique well understood as regardsconcrete structures and previously never considered in connection withmastic structures, due perhaps because of the normally nonadherentcharacter of. mastic and cement structures, may be appliedto masticstructures to the great improvement of the finished structure byimparting new, useful, unexpected and previously unknown-qualities tosuch mastic structures.

It should be noted that in carrying out the method of treatment ofmastic structures proposed herein, substantially all of the desirablequalities of the mastic structure are retained, as for example, lowcost, low heat and sound transmission, resiiiency, etc., and thefinished structure is especially vwell adapted for floors, beingcomfortableand apparently warm underfoot.

The quality of both the mastic structure and the cement surface thereof,may be improved by treatingthe same prior to setting --with a colored oruncolored emulsion of wax in water, such as disclosed in my U. S. PatentNo. 1,958,397 issued May 8, 1934. This treatment improves the curing ofboth the mastic structure and its cement surface while at the same timepreventing staining of such surface because of'its being impregnatedwith a coating of wax which may be readily cleaned and polished.

Fm'thermorait is to be understood that the particular compositions andprocesses shown and described, and the particular procedure set forthare presented for purposes of illustration and ex- Planation and thatvarious modifications of said ed October 6, 1924, t0-

Aggregate for concrete.

aoeaeis compositions, processes and procedure may be made withoutdeparture from the invention as defined in the appended claims.

Having thus described my invention what I claim is:

i. The ,process of hardening the-surface of a structure formed from amastic composition emulsified in an aqueous medium which consists inapplying to the damp surface of such structure prior to its setting adry mixture of hydraulic cement and small irregularly shaped metallicparticles, working the same into the surface of said structure, andfinally troweling the same to a smooth compact surface.

2. The process of treating the surface of a structure formed from amastic composition emulsified in an aqueous medium which consists inapplying to the damp surface of such structure prior to its setting adry mixture of hydraulic cement and small irregularly shaped metallicparticles, working the same into the surface of said structure,troweling the same to a smooth compact surface, and finally coating thesame with an emulsion of wax in water.

3. The process of hardening the surface of a structure formed from amastic composition emulsified in an aqueous medium which consists inapplying to the damp surface of such structure prior to its setting adry mixture comprising hydraulic cement, small irregularly shapedmetallic particles and a small quantity ,of an organic plasticizingagent, working the same into the surface of said structure, and finallytroweling the same to a smoothly finished surface.

4. The process of hardening the surface of a structure formed from amastic composition emulsified in an aqueous medium which consists infirst applying to the surface of said structure prior to its setting alayer of hydraulic cement containing fine, irregularly shaped grains ofmetal, next thoroughly rubbing the same into contact with saidstructure, then troweling said surface to a smooth finish, and lastlymaintaining said surface in aunoist condition until said masticstructure and its surface has hardened and set. 9

5. The process of hardening the surface of a structure formed from amastic compositionemulsified in an aqueous medium which co ists inapplying to the surface of said structure prior to its setting a layerof dry hydraulic cement containing finely comminuted metallic particlesand afterward rubbing and troweling the same into contact with saidmastic structure until said layer has become thoroughly wetted by themoisture from the mastic structure and the iron particles have becomeinterlocked with said structure and incased fivith cement paste.

6. The process of hardening and rendering impervious, wear-proof andimpenetrable the surface 'of a structure formed from a masticcomposition emulsified in an aqueous medium which consists in applyingto the surface of saidstructure prior to its setting a dry layer ofhydraulic cement and finely divided metallic particles in proportions byweight of approximately one part of cement to two parts of iron, andthoroughly troweling such layer upon the surface of said structurewhereby said layer and said structure may become merged with each otherand said iron particles firmly interlocked together.

'7. The process of surfacing a structure which consists in applying tothe surface of said structure a bonding coat of asphalt primer, nextapplying to the asphalt coating an emulsified asphalt mix, tamping,leveling and floating such mix, and then applying to the surface of suchmix prior to its setting a dry mixture of hydraulic cement and finelycomminuted metallic particles, and afterward rubbing and troweling thesame into contact with said asphalt mix.

8. The process of surfacing a concrete structure which consists inapplying to the surface of the concrete a bonding coat of asphaltprimer, next applying to the asphalt coating an emulsified asphalt mix,tamping, leveling and floating such mix, and then applying to thesurface of such mix prior to its setting a dry mixture of hydrauliccement and finely comminuted metallicparticles, and afterward rubbingand troweling the same into contact with said asphalt mix.

9. The process of integrally forming a structure having a hard, dense,-.wear resistant surface with a bodyformed from a relatively softmaterial of low mechanical strength which comprises forming the body ofthe structure from a mixture including emulsified asphalt as a binderand surfacing such mixture prior to its setting with a mixture of dryhydraulic cement and finely divided particles of metal and working suchpar.- ticles into the surface of the structure so as to provide a hard,dense, smoothlyfinished surface thereon.

10. An integrally formed structure comprising a body of relatively softmaterial having a relatively hard surface formed from a material whichnormally will not adhere to such soft material, and means includingsmall particles of matter the dimensions of which are substantiallyone-eighth of an inch or less partially embedded in both such materialsfor bonding the hard surface, to the softer body of the structure, suchparticles forming an integral part of said hard surface and pen- Ietrating the soft material of said body.

11. Anintegrally formed structure comprising a body of relatively softmaterial having a relatively hard surface formed from a material whichnormally will not adhere to such soft material, and small metallicparticles whose dimensions generally do not exceed one-eighth of an inchpartially embedded in both such materials for bonding the hard surfaceto the softer body of the structure, such particles forming an integralpart of said hard surface and penetrating the soft material of saidbody.

12. An integrally formed structure comprising a body of relatively softmaterial including an organic binder and having a relatively hardsurface formed from a material including an inorganic binder whichnormally will not adhere .to such soft material, and means includingsmall discrete particles of matter the dimensions of which aresubstantially one-eighth of an inch or less, partially embedded in bothsuch materials for bonding the hard surface to the softer body of thestructure, such particles forming an integral part of said hard surfaceand penetrating the soft material of said body. 7

13. An integrally formed laminated structure comprising a relativelysoft base or body portion held together .by an asphalt binder having ahard outer surface held together by a hydraulic cement binder, and meansincluding small discrete particles of matter the dimensions of which aresubstantially one-eighth of an inch or less for bonding said surface tosaid body portion.

14. An integrally formed laminated structure comprising a relativelysoft base or body portion ticles whose dimensions generally do notexceed one-eighth of an inch partially embedded in the surface of saidbody portion and held together by a hydraulic cement binder.

15. An integrally formed structure comprising a relatively soft masticbody with a. relatively hard normally non-adherent cement suriaceintimately bonded thereto by means of particles of metal some or whichare embedded partly in said cement and partly in said mastic body, saidparticles of metal being of relatively small size the dimensions ofwhich generally do not exceed oneeighth 01' an inch.

EDWARD W. SCRIPIURE, JR.

